The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 08, 1994
Filed:
Jun. 08, 1993
Takashi Ebata, Yokohama, JP;
Hiroshi Kawakami, Yokohama, JP;
Katsuya Matsumoto, Yokohama, JP;
Koshi Koseki, Yokohama, JP;
Hajime Matsushita, Yokohama, JP;
Japan Tobacco Inc., Tokyo, JP;
Abstract
An acid addition salt of .delta.-aminolevulinic acid is prepared in such a way that tetrahydrofurfurylamine (VI) is reacted with phthalic anhydride under an anhydrous condition to introduce a phthal group which protects amino group of tetrahydrofurfurylamine to give N-tetrahydrofurfuryl phthalimide (III), carbon atoms of the first- and fourth-positions of thus obtained N-tetrahydrofurfurylphthalimide (III) are oxidized at 80.degree. C. using sodium periodate as a oxidizing agent and ruthenium chloride hydrate as a catalyst to yield 5-phthalimidolevulinic acid (II), then the protecting group of 5-phthalimidolevulinic acid (II) is deprotected using an acid to prepare an acid additional salt of .delta.-aminolevulinic acid. The acid additional salt of .delta.-aminolevulinic acid is readily converted by neutralization by an alkali to .delta.-aminolevulinic acid, which is very useful as a precursor of Vitamin B.sub.12, heme and chlorophyll.